U.S. patent number 11,355,280 [Application Number 16/658,897] was granted by the patent office on 2022-06-07 for coil unit.
This patent grant is currently assigned to TOYOTA JIDOSHA KABUSHIKI KAISHA. The grantee listed for this patent is Toyota Jidosha Kabushiki Kaisha. Invention is credited to Toru Nakamura.
United States Patent |
11,355,280 |
Nakamura |
June 7, 2022 |
Coil unit
Abstract
A power-transmission-side coil unit includes: a housing
including a metal case body and a resin cover, an electric device
provided in the housing, a metal substrate disposed between the
cover and the electric device and covering the electric device, and
a power transmission coil. The case body includes a base portion,
and a ring-shaped wall portion protruding toward the cover along
the outer peripheral edge of base portion inside the outer
peripheral edge of base portion. The metal substrate includes a
partition wall disposed between the cover and the electric device,
and a peripheral wall extending from the partition wall toward the
base portion. An end portion of the peripheral wall is disposed in
the D direction relative to the upper face of the ring-shaped wall
portion. At least part of a lateral face of the peripheral wall is
in contact with a lateral face of the ring-shaped wall portion.
Inventors: |
Nakamura; Toru (Toyota,
JP) |
Applicant: |
Name |
City |
State |
Country |
Type |
Toyota Jidosha Kabushiki Kaisha |
Toyota |
N/A |
JP |
|
|
Assignee: |
TOYOTA JIDOSHA KABUSHIKI KAISHA
(Toyota, JP)
|
Family
ID: |
70280949 |
Appl.
No.: |
16/658,897 |
Filed: |
October 21, 2019 |
Prior Publication Data
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|
|
|
Document
Identifier |
Publication Date |
|
US 20200126717 A1 |
Apr 23, 2020 |
|
Foreign Application Priority Data
|
|
|
|
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Oct 23, 2018 [JP] |
|
|
JP2018-199282 |
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H02J
7/0013 (20130101); H02J 50/70 (20160201); B60L
53/12 (20190201); H02J 50/12 (20160201); H01F
27/32 (20130101); H02J 7/025 (20130101); H01F
27/363 (20200801); H02J 5/005 (20130101); H01F
27/306 (20130101); H01F 38/14 (20130101); H01F
27/36 (20130101); H01F 27/02 (20130101); H02J
2207/50 (20200101); Y02T 90/14 (20130101); Y02T
10/7072 (20130101); B60L 2270/147 (20130101); Y02T
10/70 (20130101) |
Current International
Class: |
H01F
38/14 (20060101); B60L 53/12 (20190101); H02J
5/00 (20160101); H01F 27/32 (20060101); H02J
7/02 (20160101); H02J 50/70 (20160101); H02J
50/12 (20160101); H01F 27/30 (20060101); H01F
27/36 (20060101) |
Field of
Search: |
;320/108 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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|
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S51-028882 |
|
Jul 1976 |
|
JP |
|
2007-103749 |
|
Apr 2007 |
|
JP |
|
2007-324469 |
|
Dec 2007 |
|
JP |
|
2018-018926 |
|
Feb 2018 |
|
JP |
|
Primary Examiner: Dinh; Paul
Attorney, Agent or Firm: Dinsmore & Shohl LLP
Claims
What is claimed is:
1. A coil unit comprising: a housing including a metal body, and a
resin cover covering the metal body; an electric device provided in
the housing; a metal substrate disposed between the cover and the
electric device and covering the electric device; a coil provided
in the housing; and a shield provided in the housing, the metal
substrate including a partition wall disposed between the cover and
the electric device, and a peripheral wall extending from the
partition wall toward the metal body, the coil being disposed
between the partition wall and the cover, the shield being disposed
ahead of a part in a leak direction, the part being a part at which
the metal body faces an end portion of the peripheral wall, the
leak direction being a direction from inside to outside of the
housing at the part, the end portion being disposed in a direction
of the metal body relative to a surface of the shield that faces
the cover, at least a part of a surface of the peripheral wall that
faces the shield being in contact with the shield.
2. The coil unit according to claim 1, wherein the end portion is
disposed in the direction of the metal body relative to a surface
of the electric device that faces the metal body.
3. The coil unit according to claim 1, wherein the end portion is
in contact with the metal body.
4. The coil unit according to claim 1, wherein the metal body has a
recess, and the end portion is inserted in the recess.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
This nonprovisional application claims priority to Japanese Patent
Application No. 2018-199282 filed on Oct. 23, 2018 with the Japan
Patent Office, the entire contents of which are hereby incorporated
by reference.
BACKGROUND
Field
The present disclosure relates to a coil unit for use in wireless
power transmission.
Description of the Background Art
Japanese Patent Laying-Open No. 2018-18926 discloses a wireless
power transmission system that wirelessly transmits power from a
power-transmission-side coil unit to a power-reception-side coil
unit. The power-transmission-side coil unit disclosed in Japanese
Patent Laying-Open No. 2018-18926 includes a housing including a
metal body and a resin cover, a power transmission coil, a metal
substrate for blocking an electromagnetic wave generated by the
power transmission coil, and an electric device including a
capacitor. The body includes a base portion, and a ring-shaped wall
portion rising up from the outer peripheral edge of the base
portion toward the resin cover. The electric device is disposed on
the base portion. The metal substrate is supported by the
ring-shaped wall portion and a support wall provided on the base
portion.
SUMMARY
The electric device contained in the housing generates an
electric-field noise. The electric-field noise is prevented from
leaking out of the housing. The coil unit disclosed in Japanese
Patent Laying-Open No. 2018-18926 includes a space in which the
electric device is covered with the body of the housing and the
metal substrate. However, there may be a gap between the metal
substrate and the body (the ring-shaped wall portion). If such a
gap is formed, the electric-field noise generated from the electric
device may leak out of the housing through the gap without being
blocked.
The present disclosure has been made to solve such a problem. An
object of the present disclosure is to reduce the leak of the
electric-field noise generated from the electric device contained
in the housing to the outside of the housing.
The coil unit according to the present disclosure includes: a
housing including a metal body, and a resin cover covering the
metal body; an electric device provided in the housing; a metal
substrate disposed between the cover and the electric device and
covering the electric device; a coil provided in the housing; and a
shield provided in the housing. The metal substrate includes a
partition wall disposed between the cover and the electric device,
and a peripheral wall extending from the partition wall toward the
metal body. The coil is disposed between the partition wall and the
cover. The shield is disposed ahead of a part in a leak direction,
the part being a part at which the metal body faces an end portion
of the peripheral wall, the leak direction being a direction from
inside to outside of the housing at the part. The end portion is
disposed in the direction of the metal body relative to a surface
of the shield that faces the cover. At least a part of a surface of
the peripheral wall that faces the shield is in contact with the
shield.
According to the above-described configuration, the electric device
is covered with the metal body, the shield, and the metal
substrate. The end portion of the peripheral wall of the metal
substrate is disposed in the direction of the metal body relative
to the surface of the shield that faces the cover, and at least a
part of the surface of the peripheral wall that faces the shield is
in contact with the shield. This can block the path through which
the electric-field noise generated from the electric device
directly leaks from the region covered with the metal body, the
shield, and the metal substrate. Thus, the electric-field noise
generated from the electric device is reflected by the metal body,
the shield, and the metal substrate. When the electric-field noise
is reflected by the metal substrate and the like, a reflection loss
is produced and the electric-field noise is attenuated. This can
reduce the leak of the electric-field noise generated from the
electric device to the outside of the housing.
In one embodiment, the end portion of the peripheral wall of the
metal substrate is disposed in the direction of the metal body
relative to a surface of the electric device that faces the metal
body.
According to the above-described configuration, the electric-field
noise generated from the electric device is more reliably prevented
from leaking to the outside from the region covered with the metal
body, the shield, and the metal substrate. Accordingly, the
electric-field noise generated from the electric device does not
leak from the above-described region directly to the outside, and
the reflected electric-field noise also does not easily leak to the
outside of the above-described region. Thus, the electric-field
noise generated from the electric device is repeatedly reflected
and attenuated by the metal body, the shield, and the metal
substrate, thus reducing the leak of the electric-field noise to
the outside of the housing.
In one embodiment, the end portion of the peripheral wall of the
metal substrate is in contact with the metal body.
According to the above-described configuration, the electric-field
noise generated from the electric device is still more reliably
prevented from leaking to the outside from the region covered with
the metal body, the shield, and the metal substrate. Accordingly,
the electric-field noise generated from the electric device does
not leak from the above-described region directly to the outside,
and the reflected electric-field noise also does not easily leak to
the outside of the above-described region. Thus, the electric-field
noise generated from the electric device is repeatedly reflected
and attenuated by the metal body, the shield, and the metal
substrate, thus reducing the leak of the electric-field noise to
the outside of the housing.
Further, since the end portion of the peripheral wall of the metal
substrate is in contact with the metal body, the metal substrate is
improved in rigidity against, for example, a force applied in the
direction from the cover toward the metal body.
In one embodiment, the metal body of the housing has a recess. The
end portion of the peripheral wall of the metal substrate is
inserted in the recess.
According to the above-described configuration, the electric-field
noise generated from the electric device is still more reliably
prevented from leaking to the outside from the region covered with
the metal body, the shield, and the metal substrate. Accordingly,
the electric-field noise generated from the electric device does
not leak from the above-described region directly to the outside,
and the reflected electric-field noise also does not easily leak to
the outside of the above-described region. Thus, the electric-field
noise generated from the electric device is repeatedly reflected
and attenuated by the metal body, the shield, and the metal
substrate, thus reducing the leak of the electric-field noise to
the outside of the housing.
Further, since the end portion of the peripheral wall of the metal
substrate is in contact with the metal body, the metal substrate is
improved in rigidity against, for example, a force applied in the
direction from the cover toward the metal body.
A coil unit according to the present disclosure includes: a housing
including a metal body, and a resin cover covering the metal body;
an electric device provided in the housing; a metal substrate
disposed between the cover and the electric device and covering the
electric device; a coil provided in the housing; and a shield
provided in the housing. The metal substrate includes a partition
wall disposed between the cover and the electric device, and a
peripheral wall extending from the partition wall toward the metal
body. The coil is disposed between the partition wall and the
cover. The shield is disposed ahead of a part in a leak direction,
the part being a part at which the metal body faces an end portion
of the peripheral wall, the leak direction being a direction from
inside to outside of the housing at the part. The peripheral wall
is located between the electric device and the shield in the leak
direction. The end portion is disposed in the direction of the
metal body relative to a surface of the shield that faces the
cover, and in the direction of the metal body relative to a surface
of the electric device that faces the metal body.
According to the above-described configuration, the electric device
is covered with the metal body, the shield, and the metal
substrate. The end portion of the peripheral wall of the metal
substrate is disposed in the direction of the metal body relative
to the surface of the shield that faces the cover, and in the
direction of the metal body relative to the surface of the electric
device that faces the metal body. This can block the path through
which the electric-field noise generated from the electric device
directly leaks from the region covered with the metal body, the
shield, and the metal substrate. Thus, the electric-field noise
generated from the electric device is reflected and attenuated by
the metal body, the shield, and the metal substrate. This can
reduce the leak of the electric-field noise generated from the
electric device to the outside of the housing.
A coil unit according to the present disclosure includes: a housing
including a metal body, and a resin cover covering the metal body;
an electric device provided in the housing; a metal substrate
disposed between the cover and the electric device and covering the
electric device; and a coil provided in the housing. The metal
substrate includes a partition wall disposed between the cover and
the electric device, and a peripheral wall extending from the
partition wall toward the metal body. The coil is disposed between
the partition wall and the cover. The metal body has a recess. An
end portion of the peripheral wall is inserted in the recess.
According to the above-described configuration, the end portion of
the peripheral wall of the metal substrate is inserted in the
recess in the metal body. Thus, the electric device is covered with
the metal body and the metal substrate. This can block the path
through which the electric-field noise generated from the electric
device directly leaks from the region covered with the metal body
and the metal substrate, thus preventing the electric-field noise
from leaking to the outside. Thus, the electric-field noise
generated from the electric device is reflected and attenuated by
the metal body and the metal substrate without leaking from the
above-described region directly to the outside. This can reduce the
leak of the electric-field noise generated from the electric device
to the outside of the housing.
The foregoing and other objects, features, aspects and advantages
of the present disclosure will become more apparent from the
following detailed description of the present disclosure when taken
in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a general view of a wireless power transmission system to
which a power transmission apparatus according to an embodiment is
applicable.
FIG. 2 is a diagram showing an electrical configuration of a
wireless power transmission system.
FIG. 3 is an exploded perspective view of a power-transmission-side
coil unit according to an embodiment.
FIG. 4 is a plan view of a power-transmission-side coil unit.
FIG. 5 is a diagram schematically showing the V-V cross section of
a power-transmission-side coil unit.
FIG. 6 is a diagram schematically showing the V-V cross section of
a power-transmission-side coil unit according to a comparative
example.
FIG. 7 is a diagram schematically showing the V-V cross section of
a power-transmission-side coil unit according to variation 1.
FIG. 8 is a diagram schematically showing the V-V cross section of
a power-transmission-side coil unit according to variation 2.
FIG. 9 is a diagram schematically showing the V-V cross section of
a power-transmission-side coil unit according to variation 3.
FIG. 10 is a diagram schematically showing the V-V cross section of
a power-transmission-side coil unit according to variation 4.
FIG. 11 is a diagram schematically showing the V-V cross section of
a power-transmission-side coil unit according to variation 5.
DETAILED DESCRIPTION
Hereinafter, the present embodiment is described in detail with
reference to the drawings. In the drawings, identical or
corresponding parts are identically denoted, and the explanation
thereof is not repeated.
<General Configuration>
FIG. 1 is a general view of a wireless power transmission system to
which a power transmission apparatus according to the present
embodiment is applicable. With reference to FIG. 1, a wireless
power transmission system 1 includes a vehicle 2 and a
power-transmission-side coil unit 3. Power-transmission-side coil
unit 3 is installed on the ground.
Hereinafter, in a parking space where power-transmission-side coil
unit 3 is installed, the direction of movement of vehicle 2 is
defined as F and B directions, and the up and down directions
relative to the ground are respectively defined as U and D
directions. Although not shown in FIG. 1, the right and left
directions relative to vehicle 2 in a parking space are
respectively defined as R and L directions. Hereinafter, the U
direction may be simply referred to as "upper side", "upper face"
and the like, and the D direction may be simply referred to as
"lower side", "lower face" and the like.
Vehicle 2 includes a power-reception-side coil unit 4 and a power
storage device 5. Power storage device 5 is provided on the lower
face of the floor panel of vehicle 2. Power-reception-side coil
unit 4 is attached to the lower face of the case of power storage
device 5.
Power-transmission-side coil unit 3 receives power supplied from an
AC power supply 80 (e.g., a commercial grid power supply).
Power-transmission-side coil unit 3 is configured to wirelessly
transmit power to power-reception-side coil unit 4 via a magnetic
field while vehicle 2 is aligned such that power-reception-side
coil unit 4 of vehicle 2 faces power-transmission-side coil unit
3.
FIG. 2 is a diagram showing an electrical configuration of wireless
power transmission system 1 shown in FIG. 1. Power-reception-side
coil unit 4 includes a resonant circuit 7, a filter 6, and a
conversion device 10. Resonant circuit 7 includes a power reception
coil 8 and a capacitor 9. Power reception coil 8 and capacitor 9
are connected to each other in series. Resonant circuit 7 has a Q
factor of, for example, 100 or more.
Filter 6 is, for example, an LC filter. Conversion device 10 is a
rectifier to convert AC power into DC power.
Power-transmission-side coil unit 3 includes a resonant circuit 14,
a filter 11, and a conversion device 15. Resonant circuit 14
includes a power transmission coil 12 and a capacitor 13. Power
transmission coil 12 and capacitor 13 are connected to each other
in series. Resonant circuit 14 has a Q factor of, for example, 100
or more. Filter 11 is, for example, an LC filter. Conversion device
15 includes an inverter.
In wireless power transmission system 1 configured as described
above, power transmission from power-transmission-side coil unit 3
to power-reception-side coil unit 4 is briefly described.
AC power is supplied from AC power supply 80 to conversion device
15. Conversion device 15 boosts the voltage of the supplied AC
power, and adjusts the frequency to a prescribed frequency (e.g.,
several tens of kHz). Filter 11 removes noise from the AC power
supplied from conversion device 15, and supplies it to resonant
circuit 14. When the AC power is supplied to resonant circuit 14,
an electromagnetic field is formed around power transmission coil
12.
When the electromagnetic field formed around resonant circuit 14
reaches power reception coil 8, a power reception current (AC
current) flows through power reception coil 8. Filter 6 removes
noise from the AC power supplied from resonant circuit 7, and
supplies it to conversion device 10. Conversion device 10 converts
the supplied AC power into DC power, and supplies the DC power to
power storage device 5.
<Power-Transmission-Side Coil Unit>
FIG. 3 is an exploded perspective view of power-transmission-side
coil unit 3 according to the present embodiment. FIG. 4 is a plan
view of power-transmission-side coil unit 3. FIG. 5 is a diagram
schematically showing the V-V cross section in FIG. 4. With
reference to FIG. 3 to FIG. 5, power-transmission-side coil unit 3
is described.
Power-transmission-side coil unit 3 includes a housing 20; and a
power transmission coil 12, a bobbin 23, a plurality of ferrite
plates 24, a metal substrate 25, and a substrate 26 contained in
housing 20.
Housing 20 includes a case body 21, and a resin cover 22 covering
case body 21. Case body 21 is made of, for example, aluminum or
aluminum alloy.
Case body 21 includes a base portion 30, a ring-shaped wall portion
31, and a plurality of support walls 32. Base portion 30 is
generally in the shape of a flat board. Base portion 30 includes a
principal surface 33 facing resin cover 22. Base portion 30 has
seats 34 and protrusions 27 at its outer peripheral edge.
Seats 34 have tapped holes 35. Bolts 42 are inserted in tapped
holes 35 so as to fix housing 20 to, for example, the ground. Other
methods of connection may be used to fix housing 20 to the
ground.
Protrusions 27 also have tapped holes 28. Bolts 48 (described
later) are inserted in tapped holes 28 so as to fix resin cover 22
to case body 21.
Ring-shaped wall portion 31 is provided on principal surface 33 of
base portion 30. Ring-shaped wall portion 31 is provided along the
outer peripheral edge of base portion 30 inside the outer
peripheral edge of base portion 30. Ring-shaped wall portion 31
protrudes toward resin cover 22 along winding axis O1 of power
transmission coil 12. A plurality of bosses 38 are provided between
ring-shaped wall portion 31 and the outer peripheral edge of base
portion 30. The plurality of bosses 38 each have a hole 39.
Ring-shaped wall portion 31 is equivalent to an example of the
"shield" according to the present disclosure.
The plurality of support walls 32 are provided on principal surface
33 of base portion 30. The plurality of support walls 32 are
disposed inside of ring-shaped wall portion 31. The plurality of
support walls 32 extend generally radially from the center of base
portion 30. The plurality of support walls 32 protrude toward resin
cover 22 along winding axis O1 of power transmission coil 12. The
height of the plurality of support walls 32 along the direction of
winding axis O1 of power transmission coil 12 is about the same as
the height of ring-shaped wall portion 31 along the direction of
winding axis O1.
Ring-shaped wall portion 31 and the plurality of support walls 32
support metal substrate 25 from the side opposite to the power
transmission coil 12 side with respect to metal substrate 25.
Substrate 26 is fixed to base portion 30 with a fixation portion
(not shown) provided on base portion 30 within ring-shaped wall
portion 31. Substrate 26 is located between principal surface 33 of
base portion 30 and metal substrate 25.
Substrate 26 has a plurality of slits 261. The plurality of slits
261 are located at the places corresponding to the plurality of
respective support walls 32. Through each of the plurality of slits
261, a corresponding one of support walls 32 extends.
Substrate 26 includes, mounted thereon, capacitor 13 of resonant
circuit 14, filter 11, conversion device 15, a circuit board (not
shown). The circuit board includes, mounted thereon, a control
device for controlling the components (such as conversion device
15), and various sensors. Capacitor 13 is arranged such that
capacitor 13 does not interfere with the plurality of support walls
32 extending through substrate 26. In the following, substrate 26
and the components (such as conversion device 15) mounted on
substrate 26 are also referred to as an "electric device" as a
general term.
Metal substrate 25 is disposed on ring-shaped wall portion 31 and
the plurality of support walls 32. Metal substrate 25 blocks the
electromagnetic wave generated by power transmission coil 12. Metal
substrate 25 intersects winding axis O1. The central part of metal
substrate 25 protrudes toward the side opposite to the substrate 26
side. The central part of metal substrate 25 protrudes away from
substrate 26. Metal substrate 25 is made of, for example, aluminum
or aluminum alloy. Metal substrate 25 will be described in detail
later.
The plurality of ferrite plates 24 are disposed on metal substrate
25, between power transmission coil 12 and metal substrate 25. The
plurality of ferrite plates 24 are radially arranged to surround
the protruding central part of metal substrate 25.
Bobbin 23 covers the plurality of ferrite plates 24 from the side
opposite to the substrate 26 side with respect to metal substrate
25. Bobbin 23 has a coil groove 43 for power transmission coil 12
to be fitted therein. Bobbin 23 has principal surfaces opposite to
each other. Coil groove 43 is disposed on one of the principal
surfaces opposite to the other that faces the plurality of ferrite
plates 24.
Bobbin 23 has a plurality of pins 16 at its outer peripheral edge.
Pins 16 protrude toward principal surface 33 of base portion 30.
Pins 16 are inserted in holes 39 in bosses 38, so that bobbin 23 is
fixed to case body 21.
Power transmission coil 12 is fitted in coil groove 43. Power
transmission coil 12 surrounds winding axis O1. In the example
shown in FIG. 3, winding axis O1 extends in the up-down direction
of the vehicle. Power transmission coil 12 is a spiral coil having
an opening 49 at its central part.
Resin cover 22 is generally in the shape of a box with its one side
in the up-down direction being open. Resin cover 22 has a plurality
of protrusions 46 at its outer peripheral edge. Protrusions 46 have
holes 47. Bolts 48 are inserted in holes 47 and tapped holes 28 in
case body 21, so that resin cover 22 is fixed to case body 21.
The electric device contained in housing 20 may generate an
electric-field noise. The electric-field noise is prevented from
leaking out of housing 20.
Accordingly, as shown in FIG. 5, metal substrate 25 according to
the present embodiment includes a partition wall 251 intersecting
winding axis O1 (FIG. 3), and a peripheral wall 252 extending from
partition wall 251 in the D direction. An end portion 252a of
peripheral wall 252 is disposed in the D direction relative to an
upper face 31a of ring-shaped wall portion 31. Further, end portion
252a is disposed in the U direction relative to a face 26a of
substrate 26 facing in the D direction. That is, in the U-D
direction, end portion 252a is located between upper face 31a of
ring-shaped wall portion 31 and face 26a of substrate 26 facing in
the D direction.
A part of a lateral face 252b of peripheral wall 252 is in contact
with a lateral face 31b of ring-shaped wall portion 31. In the
present embodiment, lateral face 252b on the side of end portion
252a is in contact with lateral face 31b of ring-shaped wall
portion 31. At the part at which end portion 252a faces base
portion 30, the direction from the inside to the outside of housing
20 (i.e., the R-L direction) is equivalent to an example of the
"leak direction" according to the present disclosure.
With metal substrate 25 formed as described above, the electric
device can be covered with case body 21 (base portion 30 and
ring-shaped wall portion 31) and metal substrate 25. Thus, the
electric-field noise generated from the electric device reflects
within the region covered with metal substrate 25 and case body 21,
without leaking from the region directly to the outside.
When the electric-field noise generated from the electric device is
reflected by the conductive shield (e.g., case body 21), a
reflection loss is produced and the electric-field noise is
attenuated.
In the above-described region, the electric-field noise is
attenuated by reflecting on case body 21 and metal substrate 25.
This can reduce the leak of the electric-field noise generated from
the electric device to the outside of housing 20.
As described above, metal substrate 25 of power-transmission-side
coil unit 3 according to the present embodiment includes partition
wall 251 and peripheral wall 252. End portion 252a of peripheral
wall 252 is disposed in the D direction relative to upper face 31a
of ring-shaped wall portion 31. A part of lateral face 252b of
peripheral wall 252 is in contact with lateral face 31b of
ring-shaped wall portion 31. With metal substrate 25 formed in such
a manner, the electric device is covered with metal substrate 25
and case body 21. Thus, the electric-field noise generated from the
electric device is reflected and attenuated by metal substrate 25
and case body 21 without leaking from the region covered with metal
substrate 25 and case body 21 directly to the outside. This can
reduce the leak of the electric-field noise generated from the
electric device to the outside of housing 20.
The configuration of power-reception-side coil unit 4 is almost the
same as that of power-transmission-side coil unit 3 inverted in the
U-D direction. Therefore, the technical idea related to the
above-described power-transmission-side coil unit 3 can be applied
to power-reception-side coil unit 4, as a matter of course. Thus,
power-reception-side coil unit 4 can also reduce the leak of the
electric-field noise generated from the electric device to the
outside of the housing.
Comparative Example
FIG. 6 is a diagram schematically showing the V-V cross section of
a power-transmission-side coil unit according to a comparative
example. With reference to FIG. 6, the configuration of metal
substrate 25 and an electric-field noise generated from an electric
device of a power-transmission-side coil unit according to the
comparative example are described.
As shown in FIG. 6, metal substrate 25 of a power-transmission-side
coil unit according to the comparative example has a peripheral
wall 253 extending from partition wall 251 toward upper face 31a of
ring-shaped wall portion 31. Peripheral wall 253 is fastened to
ring-shaped wall portion 31 with, for example, a bolt and nut (not
shown). In such a case, as shown in FIG. 6, there may be a gap G
between peripheral wall 253 and upper face 31a of ring-shaped wall
portion 31 which may cause a leak of an electric-field noise EW
generated from the electric device. Such a gap 0 may form a path
through which electric-field noise EW generated from the electric
device leaks from the region covered with metal substrate 25 and
case body 21 directly to the outside of the region. Accordingly,
electric-field noise EW generated from the electric device may
directly leak out of housing 20 without being reflected by metal
substrate 25 and case body 21.
If the electric-field noise leaks out of housing 20 without being
attenuated, it may affect other devices.
(Variation 1)
The embodiment has described an example in which, in the U-D
direction, end portion 252a of peripheral wall 252 is located
between upper face 31a of ring-shaped wall portion 31 and face 26a
of substrate 26 facing in the D direction. However, the location of
end portion 252a is not limited to this example. If a part of
lateral face 252b of peripheral wall 252 is in contact with lateral
face 31b of ring-shaped wall portion 31, end portion 252a may be
located at any place in the D direction relative to upper face 31a
of ring-shaped wall portion 31 in the U-D direction.
FIG. 7 is a diagram schematically showing the V-V cross section of
a power-transmission-side coil unit according to variation 1.
Variation 1 describes an example in which a part of lateral face
252b of peripheral wall 252 is in contact with lateral face 31b of
ring-shaped wall portion 31 and end portion 252a is in contact with
base portion 30.
End portion 252a is in contact with base portion 30 so that the
electric device is covered with metal substrate 25 and case body
21, thus more reliably preventing the electric-field noise
generated from the electric device from leaking from the covered
region to the outside. Accordingly, the electric-field noise
generated from the electric device does not leak from the
above-described region directly to the outside, and the reflected
electric-field noise also does not easily leak to the outside of
the above-described region. Thus, the electric-field noise is
repeatedly reflected and attenuated by metal substrate 25 and case
body 21. This can reduce the leak of the electric-field noise
generated from the electric device to the outside of housing
20.
Further, since end portion 252a of peripheral wall 252 of metal
substrate 25 is in contact with base portion 30, metal substrate 25
can be improved in rigidity against, for example, a force applied
from resin cover 22 in the D direction.
(Variation 2)
FIG. 8 is a diagram schematically showing the V-V cross section of
a power-transmission-side coil unit according to variation 2.
Power-transmission-side coil unit 3 according to variation 2 has a
recess 30c in base portion 30. In recess 30c, end portion 252a of
peripheral wall 252 is inserted.
Thus, the electric device is covered with metal substrate 25 and
case body 21, thus more reliably preventing the electric-field
noise generated from the electric device from leaking from the
covered region to the outside. Accordingly, the electric-field
noise generated from the electric device does not leak from the
above-described region directly to the outside, and the reflected
electric-field noise also does not easily leak to the outside of
the above-described region. Thus, the electric-field noise is
repeatedly reflected and attenuated by metal substrate 25 and case
body 21. This can reduce the leak of the electric-field noise
generated from the electric device to the outside of housing
20.
As with variation 1, variation 2 can also improve metal substrate
25 in rigidity against a force applied from resin cover 22 in the D
direction.
(Variation 3)
The embodiment has described an example in which a part of lateral
face 252b of peripheral wall 252 is in contact with lateral face
31b of ring-shaped wall portion 31. However, a part of lateral face
252b of peripheral wall 252 being in contact with lateral face 31b
of ring-shaped wall portion 31 is not an absolute limitation. If,
in the U-D direction, end portion 252a of peripheral wall 252 is
disposed in the D direction relative to face 26a of substrate 26
facing in the D direction, peripheral wall 252 may be located
between ring-shaped wall portion 31 and the outer peripheral edge
of substrate 26 in the R-L direction.
FIG. 9 is a diagram schematically showing the V-V cross section of
a power-transmission-side coil unit according to variation 3. In
variation 3, in the U-D direction, end portion 252a of peripheral
wall 252 is disposed in the D direction relative to face 26a of
substrate 26 facing in the D direction. Peripheral wall 252 is
located between ring-shaped wall portion 31 and the outer
peripheral edge of substrate 26 in the R-L direction. Such a metal
substrate 25 can also block the path through which the
electric-field noise generated from the electric device directly
leaks from the region covered with metal substrate 25 and case body
21. Accordingly, the electric-field noise generated from the
electric device is reflected and attenuated by metal substrate 25
and case body 21. This can reduce the leak of the electric-field
noise generated from the electric device to the outside of housing
20.
In variation 3, end portion 252a of peripheral wall 252 may be in
contact with base portion 30 as described in variation 1. Also,
base portion 30 may have recess 30c, with end portion 252a of
peripheral wall 252 being inserted in recess 30c, as described in
variation 2. By doing so, as with variation 1 and variation 2, the
electric-field noise generated from the electric device does not
leak directly to the outside from the region covered with metal
substrate 25 and case body 21, and the reflected electric-field
noise also does not easily leak to the outside of the
above-described region. Accordingly, the electric-field noise is
repeatedly reflected and attenuated by metal substrate 25 and case
body 21, thus reducing the leak of the electric-field noise out of
housing 20.
(Variation 4)
FIG. 10 is a diagram schematically showing the V-V cross section of
a power-transmission-side coil unit according to variation 4.
Power-transmission-side coil unit 3 according to variation 4 has
recess 31c in ring-shaped wall portion 31. End portion 252a of
peripheral wall 252 is inserted in recess 31c. Thus, the electric
device is covered with metal substrate 25 and case body 21, thus
more reliably preventing the electric-field noise generated from
the electric device from leaking from the covered region to the
outside. Accordingly, the electric-field noise generated from the
electric device does not leak from the above-described region
directly to the outside, and the reflected electric-field noise
also does not easily leak to the outside of the above-described
region. Thus, the electric-field noise is repeatedly reflected and
attenuated by metal substrate 25 and case body 21. This can reduce
the leak of the electric-field noise generated from the electric
device to the outside of housing 20.
As with variation 1 and variation 2, variation 4 can also improve
metal substrate 25 in rigidity against a force applied from resin
cover 22 in the D direction.
(Variation 5)
FIG. 11 is a diagram schematically showing the V-V cross section of
a power-transmission-side coil unit according to variation 5. In
order to reduce the direct leak of the electric-field noise
generated from the electric device out of the region covered with
metal substrate 25 and case body 21, a separate shield member 70
may be provided on metal substrate 25.
Metal substrate 25 of power-transmission-side coil unit 3 according
to variation 5 has the same configuration as that of the
comparative example. Shield member 70 is made of, for example,
aluminum or aluminum alloy. Shield member 70 is located between
ring-shaped wall portion 31 and the outer peripheral edge of
substrate 26 in the R-L direction.
One end of shield member 70 is fastened to partition wall 251
and/or peripheral wall 252 of metal substrate 25 with, for example,
a bolt and nut. The other end of shield member 70 extends from the
one end in the D direction. An end portion 70a at the other end of
shield member 70 is disposed in the D direction relative to upper
face 31a of ring-shaped wall portion 31. A part of a lateral face
70b of shield member 70 is in contact with lateral face 31b of
ring-shaped wall portion 31. Shield member 70 extends in the
front-back direction (F-B direction) in the figure.
By fastening shield member 70 to metal substrate 25 as described
above, the electric device can be covered with metal substrate 25,
shield member 70, and case body 21. This can block the path through
which the electric-field noise generated from the electric device
directly leaks from the region covered with metal substrate 25,
shield member 70, and case body 21. Accordingly, the electric-field
noise generated from the electric device is reflected and
attenuated by metal substrate 25, shield member 70, and case body
21. This can reduce the leak of the electric-field noise generated
from the electric device to the outside of housing 20.
Variation 5 can be combined with any of variations 1 to 4. Any of
such combinations can also bring about the same advantageous
effects as those of variations 1 to 4.
Although variation 5 has described an example in which shield
member 70 is provided as a separate member, shield member 70 may be
integrated with metal substrate 25.
(Variation 6)
The embodiment has described an example in which case body 21
includes base portion 30 and ring-shaped wall portion 31, with
ring-shaped wall portion 31 being equivalent to an example of the
"shield" according to the present disclosure. However, another
member may be provided as the shield. The member may be made of,
for example, aluminum or aluminum alloy.
Although embodiments of the present disclosure have been described,
it should be understood that the embodiments disclosed herein are
by way of example in every respect, not by way of limitation. The
scope of the present disclosure is defined by the terms of the
claims and is intended to include any modification within the
meaning and scope equivalent to the terms of the claims.
* * * * *